Electrolysis is a technique where electricity is passed through effluent so that it can be treated. The current destabilizes the dissolved collodial particles in the effluent and alters the charge of suspended particles. This allows them to be coagulated, to float and to separate. The action of electrolysis generates hydrogen and oxygen, moves the coagulated and suspended particles to the top, and then they can be skimmed off the surface and removed.
Many sewage cleaning facilities have a sedimentation stage where the sewage is allowed to pass slowly through large tanks, known as "primary clarifiers" or "primary sedimentation tanks". The tanks are big enough so that sludge settles and floats material such as grease and oils that rise to the surface and are then skimmed off. The main purpose of the primary clarification stage is to produce both a generally homogeneous liquid capable of being treated biologically and a sludge that can be separately treated or processed. Primary settling tanks are usually equipped with mechanically driven scrapers that continually drive the collected sludge towards a hopper in the base of the tank from where it can be pumped to further sludge treatment stages.
Back to Bioremediation Assignment:SE
Back to Bioremediation Assignment